Beam compass



May 10,1927.

D. E. PRENVEILLE BEAM COMPASS Filed F'b. l2, 1925 mamy Mw M IN V EN TOR.

di.' ffm/mmm yso Patented May 10, 1927.

NETE@ STATES; PATENT k@iFiitC- DONALD E. PRENVEILLE, OF OAKLAND, CALFORIH, .ASSGNOR- OF ONE-HALF T0 ANTOINE E. M. PRENVEILLE, OFvGAKLi-LNIL CALFOR-NIA.

BEAM COMPASS.

Application filed February 12, 1925. Serial No 5,658.'

My invention relates to beam compasses having the beam thereof formedA with adjustably related sections.

An object of the' invention is to provide a device of the character described having the beam thereof provided with a handle portion for use in manipulating the device, and means associated with said handle portion for adjusting' the 'relative positions of the compass points carried by thebeam.

Another object of the invention is to providea device ofthe character described having,` meansV associated with said adjusting means for holding the relatively movable portions in desired frictional engagement.

The invention possesses other objects and features ofadvantages, some of which, Vwith the foregoing, willbe set forth in the following description of the preferred form of' my invention which is illustrated in the drawings accompanying and forming part of the specification. Itis to be understood that l do not limit myself to the showing made by the said drawings and description, as l may adopt variations of the preferred form within the scope of my invention as set forth in the claims. y

Referring to said drawings Figure 1kis a plan view of the compass of my invention;

Figure 2 is a side view of the device, partly in section. l

Figure' 8 is a4 sectional view taken on the line 3-3 in Figure 2.

As` illust-rated in the drawings, the coinpass of myinvention comprises a beam or rod 5, preferably formed in three sections 6, 7, and S. As here shown thev sections or arms 6 and 8 are provided at oppositely disposed extremities with sockets 11 and 12 respectively in which the various compass pointsv are arranged to be removably and frictionally held, a pen 13 and needle-point carrying member 111 being here shown so held in the sockets 11 and 12 respectively. Formed in the sect-ion 7 of the beam are parallel guideways 16 and 17 in which the arms 6 and 8 are slidably mounted, while extending from said section transversely upward of the plane of movement of the sections 6 and 8 is an extension 18, here shown of cylindrical form and having the upper portion 19 thereof knurled to aid in holding the same.

Means are provided as part of the device for simultaneously moving the arms 6 and 8 through their guideways.y As here kshown such means comprises a pinion gear 21 mounted in the section 7 and arranged tooperatively engage racks 22 and 23 provided on the arms 6 and 8 respectively, such racksy engaging said gear atopposite sides thereof. in this manner, it will be noted, rotation of the gear 21 will cause a corresponding simultaneous movement of the arms 6 and 8 with respect to the member 7 to thus cause the sockets 11 and 12 to approach or separate as may be desired. Rotation of the gear 21 is here shown arranged to be veffected by means of the rotation of a shaft or stem 2l which carries the gear and is mounted in a bearing 26 extending axially through the extension 18. The end 27 of the shaft 2liprcferably extends through and beyond the extension portion 19, and the exposed portion thereof is preferably lnurled to facilitate rotation by means of the lingers.

1n order` to maintain the compass points in desired relation during the use of the compass, means are provided which cooperate with the arm moving mechanism to hold the relatively movable parts of the device in fixed relation. As here shown, the member 7 is provided with a slot 28 extending longitudinally therethrough between and parallel to the guideways 16 and 17 and extending into the extension 18 to a point substantially midwayk thereof. It will now be noted that the sections of the member 7 thus .separated bv theslot 28 maybe pressed together, and that when so pressed they will force the arms 6 and 8 against the opposite sides of the gear to thereby cause frictional 'engagement of the arms in their guideways. In order to yeffect suoli inward movement of the sections of member 7, the inner portion 31 of the handle 18 is preferably provided with threads 32 terminating at the small diameter of a conical surface 33 provided at the base of the extension 1S. To cause the desired movement of the separated sections of the member 7 a lock-nut 3st is provided which is arranged to engage the threads 32 and has an inner edge portion 36 arranged to slidably engage the surface 33. nthis manner, turning of the nut 341 Aon the threads 32 to advance the same toward the base of the handle will, through its engagement with the surface 33,. force the portions of the section 7 together to provide any required frictional engagement of the soeiiions with oooh other, :is heif'eizihol'oi'e ilosil'hed, :3o that relativo n'ioveniont oil ihe soeiiono ino)`- ho hindoifod ol' entirelyT p11:- i'onleii no inziji' ne ilosioil. il `will he nol'eil ilo-ill ille hooking illl is enlarged nl; ils lower enil lo prevent gripping ol? tho shaft helol'e the Ivor is gripped.

rl`ho sioni portion QT! ohlonoion poi'lion il?? :ini'l noi' I-l, it Ywill non' ho noleil, unile lo in'ovlilo :i eeniioliji' ilioposeil honille Al'oi` the ilovii'e which nnil he :i(li'onlzigooiirily used in niiiniimlolzino; lihe sanno. ilini'helnore, with lho eoiniizn'l4 :mon i hoio Shown ziili,i;-il,1i'ieiil1 oii lfhe :irnos unil looking oi iinloilv infr ol` tho ilei'ioe moli' lio i'roilily oeeompliolioil ii/'hilo lho ooniiinss is in low with oiil uoixciswil'niing; Vio i'oporfiilioninf" ol' llio honil on tho ilvviee oif i'eiiioi'iill;h lhe giix'ol' `noinl' Vi'oni ilo poi-:ilion on l'lie n'oih. 'lhon too, :ingu wein' olf liio 15mm-5 o1- oliiflino; hemwhioh only owin nini' he iohon np hy iii-1o oli lhe loixlinni Pil, no l'lon wein' loon nol*` izniniii The elliifiengy o'i" llio ileiife.

in (he oi'onl" i'hziil il, in iiefiii'eil l'o change lho Violino ol lhe im: lo lio ili'own :ihoni :i rivoli contea; :ind :il (he mino linie hoop lho houille ioini out in ilnl Conlon inieioml olf mino; (he nlmi'i. :o: the oi'io-:iiijioilimg nieons in ihe nionnoi* lieioiniioioio iliw-aii'iliwl, oilioi-.ilinonl muy he niniiily eievi'i-il lo' loos eninf); lho loelmot :und iiil'eeily moving tho other :illn lo iheioliji Sei'` ille niovlioi's lho soilnii'eil iiiriinnoe onori, ili lieinglj noleil, limi? liiy i'eoion ol"A ilio gem lh@ :ii'nm unil eenll'zll inoinhoi' i will niziinloin llioiiinfonet roloiion. li`lii'llieiiiioi'o ii' will ho ohiioori that the oL'n'iS nini readily lio i'eiihiooil with lon ;e1 or @hoi-lei onori. im doeii-oilK so llnil; lhe` (lo vico im :iiloplolile l'oi` noe *l'oi i wiilo rango ol' wolli.

V1 A l.)ziniwoniiizwsi i'oiil oolnpi'ioinf: :i hoilv iofjainhei;` on :mn -'li lohlj,i inonnleil in ooi( nionihei, o nnunioll).y i'oizil'nhio shalt monntoiii in oiiii'l nienihoi, o pinion nioonlod on, Suhl olioi'i". l'ho umn hovinn' o roel( operail'ii'oly eiigfnginitg Suini pinion, :imi menno ezirrioni by Suid nionihei' omi oiiloptoclto ooopemte therewith io presi; the :mn and pinion ini'o iflieliiinnil ongogenionl: willi various inionsities. i i

f2. A boom-compass ifoi'l z olnprisiug :L longitudinally slotted hoilji' :inoinhoi' having? :i` guidewoy and :i shol't hooking arranged therein, on :um nionniieifl 'for movementin Suid gniilowoy, :i rotatable shnlt monnloil in Suid hioring, nlozlns operable npon the i'o l'oi'ion ol Suhl shaft to move snirl nil'ni through Suid gnilowogz :mil :i'elocisohlo moons oi'izingeii lo ssinmlioneonsly und loi-oh lily engage soiil, al1-1n holwoen will lhsi menno :ind said nionihor.

23. hozini-oon'ipoos rod comprising o longilulinolly Hlotlod holly member having; poi'zillol giiidewoyn :mil n sholl: hearing pro-- Vidoil therein, :imno Sliclohly engaging in soirl guiilowoys, o shoflb mounted in Suid heaving, o, gooi' .lixodly mounted on said sini'lftj there heilig rocks provided on said :i1-ins and arranged to operatively engage will pinion on oppooilo oidos thereof, ond nn'iinuolljir opoi'nhlo ioloosulilo nleons oo0pei'oling' willi ihe hotly menilioi io simultaneously como tho gi'iifipilng' olf said. gen1' lietween [lio :mno :uni the friotionol ongago inonl of will :mns the woll ol'` tilioii.' guido woy. i

A lioommompaos roi] comprising Sliflsilnly engogeil sections, :in extension pro i'iiloifl on one o l' .sniil soelions, `manually eonfrolleil i'otnl'olile moons osli'x'iol. hy Said ex tension :1mi nilo-ngg'oii lo :nove liho other Soeiion Vehilivo thereto, :nonno on llhe noe.- iion having saiiil extension whereby the lool@ iiiig iojijei'hoi' ol* lhe sections 111:15` ho of?- 'Foote/(i, oni] manually controlled. ronl'oblo 1 means mounted on sind oxtonssion in ooneontiio i'eiotaion with soiil lil-sommano und opei'zilile in eoope olLion with salici lost .moons l'o lool; #oid .oei-tions in lixofl rohition.

in toslil'iiooy whoi'ool", I .have hereunto Set my honil :it Ooklonil, (,luili'foi'nin5 this Qlth doy of January, 1.925.

DONA LD E. lcRENVElI/l?)d 

